[docs.mifos.org] Create/Update empty pages

[tapaswenipathak]

Add/create/update information on empty docs.mifos.org pages:

• https://docs.mifos.org/general-contributing-guidelines/contribution-guidelines-for-an-android-project
  Outline: https://paper.dropbox.com/doc/Outline-Contribution-Guidelines-Android-Project--BlQXMiKlL1toy20xnFYPmQk8AQ-2U7I0Zr3mDM6fVNOCQCN1
• https://docs.mifos.org/getting-started/getting-started-with-git-github
  Outline: https://paper.dropbox.com/doc/Outline-Getting-started-with-Git-Github--BlSwMbO__Lr4ZL1PgNMDgSxvAQ-tIIntbgv9eUGPWynl0N2T
• https://docs.mifos.org/general-contributing-guidelines/contribution-guidelines-for-a-web-project
  Outline: https://paper.dropbox.com/doc/Outline-Contribution-Guidelines-Web-Project--BlzdJth5P71TXA5qMVR8REh1AQ-dI1nJGXmr8ioF6WOLqJHv
• https://docs.mifos.org/mifosx/developer-space/contributors-guide
  Outline: https://paper.dropbox.com/doc/Outline-Contributors-Guide--BlyYDnfq6yVCNFD01zRbtIw6AQ-dIhVfiKbp25fRhUEw5ll0
• https://docs.mifos.org/general-contributing-guidelines/upstream-first-approach
  Outline: https://paper.dropbox.com/doc/Outline-Upstream-Development-Approach--BlzstdBW_HdhZ5pRlhH823VgAQ-I4mMVLFVAFtEYIHx613WX
• https://docs.mifos.org/general-contributing-guidelines/upstream-first-approach/contribution-process

cc @edcable.