Documented pseudofield property of filters.

Corrected errors in and reorganized hook_civicrm_apiWrappers() documentation

don't include deprecated attribute in example

clarify meaning of is_contact and is_domain

Update hook_civicrm_aclWhereClause.md

Remove 4.4 references - too old now

Update hook_civicrm_aclWhereClause.md

removed reference to the LTS

Ripped out some old stuff

Update bootstrap.md

Add hook_civicrm_findDuplicates documentation

Add explanation about interactive rebasing

I didn't add in the ESR as I don't believe the policy  is clear enough to be documented but generally I understand that the discussion takes place on the ESR channel & PRs are not really encouraged against the branch - the CT would do a PR if they decide to backport or agree someone else would

Clarify that the ContactID refers to the user making the query - my reading had been that it was the contact ID of the contact that was being considered.

Explain what the `$type` parameter means/relates to.

Update hook_civicrm_permission_check.md

Formatting tweak

Add note about custom data on any creation

Resolve #577 Fix URL pointing to how to set up extension directory

- Updated incorrect interface method name.
- Reorganized to match the de facto standard apparent on other hook pages.
- General content improvements.

Add in notes about support for KeyColumn parameter when using option …

Added additional headings to facilitate more precise linking

Fix bad link/duplicate text.

Add missing variables to hook_civicrm_export

Add in notes about support for KeyColumn parameter when using option group as part of a setting pseudoconstant

Fleshed out validate_callback doc.

Describe new variables due to dev/core#457