Add jut and nopagebreak as panel options

[kylebaron]

Summary

• add jut argument to rowpanel() to shift non-panel rows; units are ex
• add nopagebreak argument to rowpanel(); default is TRUE and results in \\* getting added to panel rows to when rendering longtable prevent page breaks (in longtable environment only)
• panel rows are marked by a commented tag, stored in the .internal environment
• Filled in documentation for longtable and added simple example

Example - jut

Example - nopagebreak

> stable_long(data1, panel = "STUDY")
....                                                                 
[11] "\\hline"                                                                        
[12] "DOSE & FORM & N & WT & CRCL & AGE & ALB & SCR \\\\"                             
[13] "\\hline"                                                                        
[14] "\\endfirsthead"                                                                 
[15] "\\hline"                                                                        
[16] "DOSE & FORM & N & WT & CRCL & AGE & ALB & SCR \\\\"                             
[17] "\\hline"                                                                        
[18] "\\endhead"                                                                      
[19] "\\hline"                                                                        
[20] "\\multicolumn{8}{l}{\\textbf{12-DEMO-001}}\\\\*%--pmtables-insert-panel"        
[21] "100 mg & tablet & 80 & 71.4 & 104 & 33.7 & 4.20 & 1.06 \\\\"                    
[22] "150 mg & capsule & 16 & 89.4 & 122 & 24.4 & 4.63 & 1.12 \\\\"                   
[23] "150 mg & tablet & 48 & 81.7 & 104 & 34.4 & 3.83 & 0.910 \\\\"                   
[24] "150 mg & troche & 16 & 94.0 & 93.2 & 27.4 & 4.94 & 1.25 \\\\"                   
[25] "200 mg & tablet & 64 & 67.9 & 100 & 27.5 & 4.25 & 1.10 \\\\"                    
[26] "200 mg & troche & 16 & 76.6 & 99.2 & 22.8 & 4.54 & 1.15 \\\\"                   
[27] "\\hline \\multicolumn{8}{l}{\\textbf{12-DEMO-002}}\\\\*%--pmtables-insert-panel"
[28] "100 mg & capsule & 36 & 61.3 & 113 & 38.3 & 4.04 & 1.28 \\\\"                   
[29] "100 mg & tablet & 324 & 77.6 & 106 & 29.9 & 4.31 & 0.981 \\\\"                  
[30] "50 mg & capsule & 36 & 74.1 & 112 & 37.1 & 4.44 & 0.900 \\\\"                   
[31] "50 mg & tablet & 324 & 71.2 & 106 & 34.1 & 4.63 & 0.868 \\\\"                   
[32] "75 mg & capsule & 36 & 72.4 & 105 & 38.2 & 3.89 & 0.900 \\\\"                   
[33] "75 mg & tablet & 288 & 71.6 & 98.9 & 34.2 & 4.49 & 0.991 \\\\"                  
[34] "75 mg & troche & 36 & 73.6 & 103 & 49.2 & 4.52 & 0.930 \\\\"                    
[35] "\\hline"                                                                        
[36] "\\end{longtable}"                                                               
attr(,"class")
[1] "stable_long" "stable"