Registration should not assume there is an oldblob

This change checks first if we have an old blobvault configured, and
only issues the remove command in that case.
[FEATURE] trade: show account on hover over orders in the order book
[FIX] index: remove extra welcome banners
[FIX] Register: text fixes, try 2
[CHORE] Migration flow: Update copy during flow (RT-1880)
Merge pull request #1289 from annatonger/fix/textfixtry2

[FIX] Register: text fixes, try 2
Merge pull request #1290 from yongsoo/feature/migration

[CHORE] Migration flow: Update copy during flow (RT-1880)
Merge pull request #1287 from shekenahglory/release

[FEATURE] trade: show account on hover over orders in the order book
[CHORE] Activity: Remove unused activity page
Merge pull request #1291 from vhpoet/release

[CHORE] Activity: Remove unused activity page
[CHORE] l10n: Update japanese translation
Merge pull request #1292 from vhpoet/release

[CHORE] l10n: Update japanese translation
[CHORE] l10n: string changes
Merge pull request #1293 from vhpoet/release

[CHORE] l10n: string changes
[FIX] Exchange: fix pathfinding for demmurage
Merge pull request #1294 from vhpoet/release

[FIX] Exchange: fix pathfinding for demmurage
Bump version to 1.0.0
[FIX] Removed the local remembering of non-default currencies
[FIX] RT-1929 Fixed loading of currency pairs
[TASK] Moved function to utils