Refactor Process struct

[trizinix]

We can't prefetch all the properties for the user. We shouldn't be inconsistent if a property is prefetched or up-to-date. Hence we have to return always an up-to-date value. The Process should be an opaque data type and we should provide the following methods to fetch the relevant property.

• [ ] process_pid
• [ ] process_ppid
• [ ] process_name
• [ ] process_exe
• [ ] process_cmdline
• [ ] process_create_time
• [ ] process_parent
• [ ] process_cwd
• [ ] process_username
• [ ] process_uids
• [ ] process_gids
• [ ] process_terminal
• [ ] process_nice
• [ ] process_ionice
• [ ] process_rlimit
• [ ] process_io_counters
• [ ] process_num_ctx_switches
• [ ] process_num_fds
• [ ] process_num_handles
• [ ] process_num_threads
• [ ] process_threads
• [ ] process_cpu_times
• [ ] process_cpu_percent
• [ ] process_cpu_affinity
• [ ] process_memory_info
• [ ] process_memory_info_ex
• [ ] process_memory_percent
• [ ] process_memory_maps
• [ ] process_children
• [ ] process_open_files
• [ ] process_connections
• [ ] process_is_running
• [ ] process_send_signal
• [ ] process_suspend
• [ ] process_resume
• [ ] process_terminate
• [ ] process_kill
• [ ] process_wait

[nibrahim]

Agreed. I made a mention of this in README.