Integrate GARDEL

[chinmaychinara91]

[WORK IN PROGRESS. DESCRIPTION WILL BE UPDATED]

About GARDEL: link

Test data: link

• [x] GARDEL as plugin
• [x] Automatic sEEG Contact Localization and Labeling using GARDEL (within Brainstorm)
• [x] Start GARDEL standalone GUI from Brainstorm
• [x] Create temporary folder for loading things back from GARDEL to Brainstorm subject
• [ ] Once done with GARDEL tool, load data back to Brainstorm

[chinmaychinara91]

https://github.com/brainstorm-tools/brainstorm3/pull/731/commits/165e5dc73a388b77e2c1d9d371d6aac72b6493bf merge captures important bug fixes for iEEG Panel based on PR https://github.com/brainstorm-tools/brainstorm3/pull/710